Transaction Isolation Level Auditor

Use when auditing database transaction configuration for concurrency safety — checking isolation level settings, diagnosing lost update bugs, non-repeatable read vulnerabilities, phantom read risks, or ACID compliance gaps. Applies Fowler's Table 5.1 (the explicit isolation-level × anomaly matrix from Patterns of Enterprise Application Architecture Chapter 5) to map READ UNCOMMITTED / READ COMMITTED / REPEATABLE READ / SERIALIZABLE to permitted anomaly classes: dirty read, non-repeatable read (inconsistent read), phantom read, and lost update. Produces a structured isolation audit report covering: current isolation level, permitted anomalies, code locations with read-modify-write without optimistic check (lost update vulnerability), SELECT FOR UPDATE correctness, long-transaction risks, ACID compliance at system-transaction level, and ACID gaps at business-transaction level across multiple requests. Covers: transaction isolation, database concurrency, optimistic locking, pessimistic locking, version column, READ COMMITTED default risks, REPEATABLE READ upgrade decisions, SERIALIZABLE overhead, immutability as concurrency escape hatch, Spring @Transactional isolation settings, Hibernate session isolation, SQLAlchemy transaction config, EF Core transaction isolation, business transaction ACID, saga atomicity, offline lock isolation. Triggers: 'we have a lost update bug', 'two users editing the same record', 'is our isolation level correct', 'should we use SERIALIZABLE', 'transaction audit', 'ACID compliance review'.

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Install

Claude CodeClawhHubnpxCursorCodexGemini CLI

1. Add marketplace

› /plugin marketplace add bookforge-ai/bookforge-skills

2. Install plugin

› /plugin install patterns-of-enterprise-application-architecture@bookforge-skills

3. Use the skill

› /transaction-isolation-level-auditor

CC-BY-SA · Open sourceGitHub

Source Book

Patterns of Enterprise Application Architecture

Martin Fowler, David Rice, Matthew Foemmel, Edward Hieatt, Robert Mee, Randy Stafford

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